KR20010011053A - Apparatus and method for automatically adjusting dynamicfocus - Google Patents

Abstract

PURPOSE: An apparatus for automatically controlling a dynamic focus is provided to perform a focus controlling on the basis of an image displayed on a screen of a projection television receiver, so as to exactly carry out the focus controlling according to characteristics of each projection television receiver and to automatically perform the focus controlling. CONSTITUTION: A camera(402) inputs an image displayed on a screen of a projection television receiver, and converts the image into an electrical image data signal to output the electrical image data signal. If the image data signal is received, a signal processor(502) calculates an intensity value of the image data signal corresponding to a spot, which is previously determined to measure a focus of the inputted image, and outputs the calculated intensity value. A controller(506) compares the calculated intensity value with a reference intensity value, which is calculated when a prestored normal focus is adjusted, and checks whether focuses are equal. If not, the controller(506) generates a focus controlling signal and outputs the focus controlling signal. A remote control transmitter(508) wirelessly transmits the focus controlling signal to the projection television receiver, under thecontrol of the controller(506).

Description

Dynamic Focus Automatic Control and Method {APPARATUS AND METHOD FOR AUTOMATICALLY ADJUSTING DYNAMICFOCUS}

The present invention relates to a projection television receiver, and more particularly, to an apparatus and method for automatically adjusting a dynamic focus of a projection television receiver.

In general, a projection television receiver has three cathode ray tubes for red (R), green (G), and blue (B), unlike typical TV receivers. (Cathod-ray Tube: CRT) refers to a device implemented to enable a large screen by enlarging an image formed on a large screen by magnifying an image formed on a plurality of reflectors and lenses.

FIG. 1 conceptually shows an arrangement of R, G and B cathode ray tubes and a screen provided in the projection television receiver. As shown in FIG. 1, R, G and B cathode rays are provided separately in a projection television receiver. The images projected from the tubes 100, 104, 108 are magnified through the lenses 102, 106, 110 and then merged on the screen 112 to be displayed as a single image. At this time, in the projection television receiver as described above, the focus of the center portion and the peripheral portion of the screen is changed so that the screen is not clear. To compensate for this, the conventional projection television receiver is provided with a dynamic focus control circuit.

FIG. 2 is a block diagram of a dynamic focus control circuit provided in a conventional projection television receiver, wherein the dynamic focus control circuit is horizontal through the first integrating circuit 200 and the second integrating circuit 202 in an analog manner. The synchronization signal H_sync and the vertical synchronization signal V_sync are integrated and mixed through a mixer 204 to generate and output a fixed voltage waveform necessary for dynamic focus. In this case, the fixed voltage waveform output from the conventional dynamic focus control circuit has a peak-to-peak voltage as shown in FIG. 3 unconditionally 1kv and an offset of 8kv regardless of the characteristics of the projection television receiver. The waveform is adjusted to.

That is, the conventional dynamic focus control circuit only serves to adjust the dynamic focus voltage waveform output from the mixer to the fixed voltage waveform as shown in FIG. 3, so as to adjust the dynamic focus considering the characteristics of each projection television receiver. There was a problem that can not be performed, and in the case of a projection television receiver, the same level is applied even though the focus level of the center and the edge are different, so that the focus of one side becomes out of focus.

In addition, since the dynamic focus adjustment in the conventional dynamic focus control circuit can be performed only by a hardware operation, there is a problem in that it is inconvenient in use because the user cannot easily adjust the software or the remote control.

As described above, the dynamic focus control circuit provided in the conventional projection television receiver serves to adjust a fixed dynamic focus voltage waveform to be generated, but cannot perform the dynamic focus adjustment considering the characteristics of each projection television receiver. In addition, in the case of a projection television receiver, the same level is applied even though the focus level of the center and the edge are different, so that the focus of one side does not come into focus on the other side.

It is therefore an object of the present invention to provide a dynamic focus automatic adjustment apparatus and method for automatically performing focus adjustment of a projection television receiver.

1 shows an arrangement of a cathode ray tube and a screen of a conventional projection television receiver;

2 is a block diagram of a conventional dynamic focus control apparatus;

3 is an example of a conventional dynamic focus voltage waveform;

4 is a view showing a connection configuration of the dynamic focus control apparatus according to an embodiment of the present invention,

5 is a detailed block diagram of a dynamic focus control apparatus according to an embodiment of the present invention;

6 is an exemplary test image of a 5 × 5 cross hatch pattern according to an exemplary embodiment of the present invention.

According to an aspect of the present invention, there is provided an apparatus for automatically adjusting a dynamic focus of a projection television receiver, the apparatus comprising: an image input unit configured to input an image displayed on a screen of the projection television receiver and convert the image into an electrical image data signal; A signal processor for calculating and outputting an intensity value of the image data signal corresponding to a point designated for focus measurement of the input image when receiving the image data signal output from the image input unit, and focus measurement output from the signal processor; A control unit which compares the intensity value of the image data signal of the corresponding point with a previously stored intensity value during normal focusing and checks whether or not the focus is achieved, and generates and outputs a focus adjustment signal for focusing if the focus is not achieved; , And a remote control transmitter for wirelessly transmitting the focus adjustment signal to the projection television receiver under the control of the controller.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Many specific details are set forth in the following description and in the accompanying drawings, in order to provide a more thorough understanding of the present invention. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. And a detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

4 is a diagram illustrating a system connection configuration of an apparatus for automatically adjusting dynamic focus according to an exemplary embodiment of the present invention. Referring to FIG. 4, a dynamic focus automatic adjustment system according to an exemplary embodiment of the present invention includes a projection television receiver 404 for displaying an image projected from an R, G, and B cathode ray tubes on a screen, and a projection television receiver 404. Camera 402 for receiving an image displayed on the screen 408 of the camera) and an image displayed on the screen 408 of the projection television receiver 404 inputted from the camera 402. If the display video screen is out of focus, a computer for applying the focus adjustment signal for focusing the video to the projection television receiver 404 through the remote controller 406 to adjust the dynamic focus (Personal Computer: PC) 400 It is composed of

FIG. 5 shows a detailed block diagram of the dynamic focus control apparatus of FIG. 4. Hereinafter, the operation of the dynamic focus control apparatus according to the embodiment of the present invention will be described with reference to FIG. 5.

First, the camera unit 402 inputs an image displayed on the screen 112 of the projection television receiver 404, converts it into an electric image data signal, and applies it to the PC 400. In this case, the image displayed on the screen 112 of the projection television receiver 404 may be a test image of a 5 × 5 cross hatch pattern as shown in FIG. 6. have. Accordingly, the electrical image data signal for the test image of the 5 × 5 cross hatch pattern output from the camera unit 402 is input to the signal processing unit 502 in the PC 400 through the interface unit 500. Then, the signal processor 502 calculates a voltage level, that is, an intensity value, of an image signal corresponding to an intersection point among test images of the 5 × 5 cross hatch pattern by using the image data signal, and then controls it. Is applied. Then, when the intensity value of the image signal corresponding to the intersection point of the 5 × 5 cross hatch pattern test image is calculated and input from the signal processing unit 502, the control unit 506 correctly adjusts the focus for dynamic focus adjustment. The intensity value corresponding to the readout value is read from the memory unit, and the intensity value of the input image applied from the signal processor 502 is compared. In this case, the intensity value of the video signal increases as the focus is well adjusted. The intensity value of the video signal corresponding to the intersection point of the 5 × 5 cross hatch pattern stored in the memory unit 504 in advance is increased. Is the intensity value when the desired focus is achieved.

In this case, if the intensity value at the intersection point of the input 5 × 5 cross hatch pattern is larger than the intensity value at the intersection point of the 5 × 5 cross hatch pattern stored in the memory unit 504, this is the focus of the test image. Indicates that it is well adjusted, so the controller 506 does not perform an operation for focus adjustment. On the contrary, if the intensity value at the intersection point of the input 5 × 5 cross hatch pattern is smaller than the intensity value at the intersection point of the 5 × 5 cross hatch pattern stored in the memory unit 504, the controller 506 A focus adjustment signal is generated so that the intensity value at the intersection point of the test image is equal to or greater than a preset intensity value and transmitted to the projection television receiver 404 through the remote control transmitter 508. The remote control transmission operation of the focus adjustment signal is performed only by a person who manually manipulates the focus adjustment during the production process of the conventional projection television receiver to perform the focus adjustment using the PC 400. The same applies to the case where the user performs the focus adjustment by operating the remote controller. Then, the focus adjustment signal transmitted from the remote controller 508 of the PC 400 is received through the remote controller receiver 510 of the projection television receiver 404 and applied to the convergence controller 512. The convergence control unit 512 then performs an operation according to the focus adjustment signal to generate and apply a focus current control signal to the focus rectifying circuit unit 514 to adjust the focus of the projection television receiver 404 according to the focus adjustment signal. . Accordingly, the current value applied to the focus electrodes of the R, G, and B cathode ray tubes 100, 104, and 108 in the display unit 516 through the focus rectifying circuit unit 514 is changed to adjust the focus.

Therefore, in the focus adjustment process of the conventional projection television receiver production process, the focus adjustment can be automatically performed even if a person does not manually adjust the focus while watching the test image displayed on the projection television receiver.

As described above, according to the present invention, the focus adjustment is precisely performed according to the characteristics of each projection television receiver by performing the focus adjustment based on the image displayed on the screen of the projection television receiver, and the production process by automatically performing the focus adjustment. There is an advantage in that the focus adjustment can be performed without the production staff required to adjust the focus in

Claims (3)

In the dynamic focus automatic control of the projection television receiver, An image input unit which inputs an image displayed on the screen of the projection television receiver, converts the image into an electric image data signal, and outputs the converted image signal; A signal processor for calculating and outputting an intensity value of the image data signal corresponding to a predetermined point for focus measurement of the input image when receiving the image data signal output from the image input unit; The intensity value of the image data signal of the corresponding point for focus measurement output from the signal processor is compared with a reference intensity value at the time of normal focusing, which is pre-stored to check whether focus is achieved, and if focus is not achieved, A controller for generating and outputting a focus adjustment signal; And a remote control transmitter for wirelessly transmitting the focus adjustment signal to the projection television receiver under the control of the controller. The method of claim 1, wherein the control unit, And if the intensity value of the image data signal at the corresponding point for focus measurement output from the signal processor is smaller than the previously stored intensity value during normal focusing, determining that focus is not achieved. In the dynamic focus automatic adjustment method of a projection television receiver, Converting the image displayed on the screen of the projection television receiver into an electrical image data signal; Measuring an intensity value of an image data signal corresponding to a predetermined point for focus measurement of the input image; Comparing the measured intensity value with a pre-stored reference intensity value and checking whether focus is achieved; And generating a focus adjustment signal for focusing and wirelessly transmitting to the projection television receiver when the result of the inspection is out of focus.